\documentclass[landscape]{report}
\usepackage[paperheight=4.1in,paperwidth=6in,margin=0in]{geometry}

\usepackage{pgfplots}
\usepackage{amsmath}
\usepackage{xcolor}
\pgfplotsset{compat=1.17}
\usetikzlibrary{shapes.geometric}

\begin{document}

\thispagestyle{empty}
	
\begin{figure}
	\centering
	\begin{tikzpicture}
		\begin{axis}[
			axis lines=left,
			xmin=0, xmax=1,
			ymin=-3, ymax=3,
			domain=0:1,
			samples=200,
			xtick=\empty,
			ytick={0},
			yticklabels={0},
			xlabel={$M$},
			ylabel={$f$},
			xlabel style={at={(axis description cs:1,0)},anchor=west},
			ylabel style={at={(axis description cs:-.02,.95)},  anchor=south west, rotate=-90, xshift=-0.5em},
			width=\linewidth,
			height=.7\linewidth,
			legend pos=north west,
			no markers,
			extra x ticks={0.06,0.158,0.85},
			extra x tick labels={
				{$M_0^{\ast}$},
				{$M_1^{\ast}$ \\ \small ($<\theta L_1 P_{L_1}$)},
				{$M_2^{\ast}$}
			},
			extra x tick style={tick label style={font=\normalsize, align=center}}
			]
			
			% Common slope used for the kinked lines
			\def\slope{27.2067}
			\def\xbendRight{0.779}
			\def\xstartMiddle{0.1}
			\def\xmid{0.23}
			
			% Region boundary vertical lines
			\def\xone{0.158}
			\def\xtwo{0.462}
			
			% Fill the three regions
			\draw[fill=gray!20, draw=none] (axis cs:0.001,-2.999) rectangle (axis cs:\xone,3);
			\draw[fill=gray!10, draw=none] (axis cs:\xone,-2.999) rectangle (axis cs:\xtwo,3);
			\draw[fill=gray!30, draw=none] (axis cs:\xtwo,-2.999) rectangle (axis cs:.99,3);
			
			% Thin dashed line at y=0 (no legend)
			\addplot[gray, dashed, very thin, domain=0:1, forget plot] {0};
			
			% Vertical region boundaries
			\draw[thin] (axis cs:\xone,-3) -- (axis cs:\xone,3);
			\draw[thin] (axis cs:\xtwo,-3) -- (axis cs:\xtwo,3);
			
			% -------------------------------------------------------
			% (1) Blue line: \Delta(M)
			% (2) Orange line: t(M,\lambda)
			% (3) Black line: \Delta(M) + t(M,\lambda)
			% -------------------------------------------------------
			\addplot[blue, very thick, dash pattern=on 7pt off 3pt] 
			expression {1/sqrt(0.04 + 0.96*x) - 2.5};
			\addlegendentry{$\Delta(M)$}
			
			\addplot[orange, very thick, dashed] 
			expression {4.5*x^2 + 0.1};
			\addlegendentry{$t(M,\lambda)$}
			
			\addplot[black, ultra thick] 
			expression {(1/sqrt(0.04 + 0.96*x) - 2.5) + (4.5*x^2 + 0.1)};
			\addlegendentry{$\Delta(M) + t(M,\lambda)$}

			
			% -------------------------------------------------------
			% (b) Kinked DOTTED LINES in 3 distinct colors
			% -------------------------------------------------------
			
			% 3) Olive
			\draw[cyan, dotted,very thick]
			(axis cs:0,0)
			-- (axis cs:\xbendRight,0)
			-- (axis cs:1,{(\slope)*(1-\xbendRight)});
			
			% 2) Magenta
			\draw[magenta, dotted, very thick]
			(axis cs:0,0)
			-- (axis cs:\xmid,0)
			-- (axis cs:1,{(1-\xmid)*\slope});
			
			% 1) Teal
			\draw[teal, dotted, very thick]
			(axis cs:0,0)
			-- (axis cs:0.03,0)
			-- (axis cs:1,{(1-0.03)*\slope});

			% -------------------------------------------------------
			% (a,d,e) Dots: no dashed lines, recolored, diamond shape
			% -------------------------------------------------------
			% Dot at x=0.06 -> teal
			\draw[teal, fill=teal] (axis cs:0.06,0.8162) circle (3pt);
			
			% Dot at x=0.158 -> magenta
			\draw[magenta, fill=magenta] (axis cs:0.158,0) circle (3pt);
			
			% Dot at x=0.85 -> olive
			\draw[cyan, fill=cyan] (axis cs:0.85,1.93155) circle (3pt);
			
			% White circle changed to diamond at x=0.462
			\node[diamond, draw=olive, fill=white, scale=0.7] at (axis cs:0.462,0) {};			

			% -------------------------------------------------------
			% (c) Legend entry for the 3 dotted lines (STACKED VERTICALLY)
			% -------------------------------------------------------
			\addplot [draw=gray, dotted, very thick] coordinates {(0,0)(0,0)};
			\addlegendentry{
				\quad $f^*_{\text{Banks}}(M)$
			}
			
			% Labels for the three regions
			\node[align=center,font=\footnotesize] at (axis cs:0.079,-2.5) {Sanction-Driven \\ Region};
			\node[align=center,font=\footnotesize] at (axis cs:0.31,-2.5) {Intermediate \\ Region};
			\node[align=center,font=\footnotesize] at (axis cs:0.731,-2.5) {Liquidity-Driven \\ Region};
			
		\end{axis}
	\end{tikzpicture}

	\label{fig:equilibrium}
\end{figure}



\end{document}

